Electrical connector with contact receiving channels



1968 H. B. WARZECKA 3,399,377

ELECTRICAL CONNECTOR WITH CONTACT RECEIVING CHANNELS Filed Dec. 5, 1966{2 I5 W nn g INVENTOR. Z2 FIE 4 flreaaer a. Mezzca fltmd', W {I 4 77024576 United States Patent 3,399,377 ELECTRICAL CONNECTOR WITH CONTACTRECEIVING CHANNELS Herbert B. Warzecka, New Brighton, Minn., assignor toG. T. Schjeldahl Company, Northfield, Minn., a corporation of MinnesotaFiled Dec. 5, 1966, Ser. No. 599,228 Claims. (Cl. 339-176) ABSTRACT OFTHE DISCLOSURE This invention relates to an electrical connector forprinted circuit cards. It consists of a receptacle having an elongatedslot therein bordered by a series of channels having inner and outerwalls and containing beryllium copper contacts. The contacts lay fiushagainst the outer walls of the channels and fold over so as to locatefree ends within the slot.

The present invention relates generally to an electrical connectordevice, and more particularly to a receptacle connector assembly whichis particularly adapted to receive printed circuit cards of variouswidths and thicknesses. The receptacle connector assembly design of thepresent invention provides an exceptionally thin receptacle apparatuswhich is adapted to receive cards of a variety of thicknesses, includingcards with relatively great or wide tolerance levels, and with contactbeing established with a relatively firm and uniform contact pressure.

In the design of receptacle connector assemblies, particularlyreceptacles for printed wiring or printed circuit cards, it isfrequently desirable to obtain a design which will accept cards withsubstantially wide dimensional tolerances. In order to accept a range ofcard dimensions, the design must be such as to make and establishelectrical contact consistently with this variety of card designs.Furthermore, consistent with the trend toward miniaturization, areceptacle connector assembly should normally have dimensions which areas small as is reasonably possible, consistent with the strength andelectrical requirements of the assembly. In the past, card receptaclesof various sorts have been designed which may include certain of thesedesirable features, however the receptacle design of the presentinvention combines each of these desirable features in astraight-forward design arrangement.

In accordance with the design of the receptacle connector assembly ofthe present invention, a structure is utilized wherein a receptaclechamber is available having a card receiving cavity therein, the cavitybeing provided with contact elements along oppositely disposed majorside or lateral surfaces thereof. These contact elements are arrangedalong channels which are formed in the side Walls of the receptacle, onechannel being formed along the outer surface to receive the shankportion of the contact or contact element, the other channel beingformed along the inner surface to receive the inner-connecting portionof the contact or contact elements. Between these inner and outerchannels, there is arranged a generally arcuate tip area whichaccommodates a similarly formed arcuate coupling segment along thecontact element between the shank portion of the contact and theinnerconnecting portion, and this radius formation provides for afulcrum point or flexure zone which is disposed at a substantialdistance from the actual contact area, thus providing long lever armaction with maximum deflection consistent with minimum and uniformcontact pressures. The arcuate tip is recessed from the top of the sidewall to prevent twisting of the contact from or about its axis. Inaddition, this particular design provides for a wide variety ofdispositions of the tail portion of the contacts such as may be requiredon a generally universal connector application of this type.

Therefore, it is an object of the present invention to provide animproved receptacle connector assembly which has a minimum size, andwhich is adapted to receive printed circuit cards having wide tolerancelevels. The electrical contact to the cards is uniform and consistent,this contact being with relatively uniform and low contact pressures.

It is a further object of the present invention to provide an improvedreceptacle connector assembly which is adapted to receive printedcircuit cards, the card insertion depth being maximum for the connectorsize.

It is yet a further object of the present invention to provide animproved receptacle connector assembly for receiving printed circuitcards which provides for maximum deflection of contacts along with amaximum wiping action between the contacts and the circuit boardconductors.

Other and further objects of the present invention will become apparentto those skilled in the art upon a study of the following specification,appended claims, and accompanying drawings wherein:

FIGURE 1 is a top plan view of a typical receptacle connector assemblyprepared in accordance with the present invention, the view showing aportion of the contact elements removed;

FIGURE 2 is a front elevational view of a connector of the type shown inFIGURE 1, with a portion of the contact being removed;

FIGURE 3 is an isometric view of a cut-away portion of the connectorshown in FIGURES 1 and 2, this figure being a somewhat enlarged scale,and showing an exploded relationship therewith, a printed circuit boardwhich is adapted for being received within the connector cavity; and

FIGURE 4 is an isometric view similar to FIGURE 3 showing a somewhatmodified form of arranging the tail portions of the contact within theassembly.

In accordance with the preferred modification of the present invention,particularly as shown in FIGURES 13, the receptacle connector assemblygenerally designated 10 includes a body portion 11 with a pair oflateral side walls 12 and 13 along with the end walls or lugs 1414. Thereceptacle is adapted to receive the contact 15 within the confines ofthe cavity formed between the various walls. As shown in FIGURES 1 and3, the side walls include spacer lug areas 1616 which separate theindividual contact receiving channels formed therebetween. In otherwords, the individual contacts are disposed in channels which are formedalong and within both inner and outer surfaces of the side walls betweenthe individual lugs 1616. With regard to the contact element 15, it willbe seen that each includesa tail portion 17, an outer shank portion 17a,and an inter-connecting portion 18. The individual contacts are arrangedalong the channels formed in the side walls and against the web portions19 which are disposed between the lug portions 16, these web portionsremaining between the inner and outer channels of the individual sidewalls. A bottom surface 19a, as shown in FIGURE 4, is utilized as aconnecting web between the individual side or lateral walls.

A particularly important feature of the apparatus is shown in detail inFIGURE 4, wherein the web portion 19 is shown to terminate in agenerally arcuate outer tip, such as at 19b. This tip is recessed belowthe top of the side wall. Accordingly, a portion of the contact elementor member is dispose-d over the arcuate outer tip and is provided withan arcuate coupling segment between the shank portion and the contactportion such as is shown at 21 in FIGURE 4, this coupling segment havingan inner radius which is substantially equal to the outer radius of thegenerally arcuate outer tip portion of the web 19. In other words, theradius of the tip portion 19b substantially matches the radius of thecoupling segment 21 of the individual contacts. It will be appreciatedthat these features are common between FIGURES 3 and 4, and for purposesof clarity, these details have been shown in connection with the deviceillustrated in FIGURE 4.

In forming the receptacle connector assembly of the present invention,the body portion comprising the end walls 1414, together with thespacing lugs 16, and webs 19 and 19a is initially formed. Thereafter,the individual contacts are inserted in place in the area of theindividual webs 19. Thereafter, the side walls are covered withinsulating panels such as are shown at 12 and 13. As an alternative, thepanels may be provided with inwardly extending flanges or lips to addrigidity to the structure. These individual insulating panels may beformed from a molded member consisting of a good dielectric, or may alsobe formed from a durable film material such as stress orientedpolyethylene terephthalate or the like. These panels 12 and 13 aresecured to the assembly after insertion of the individual contacttherein. Mounting holes are illustrated at either end of the device, andare formed in the end Walls, as indicated.

With attention being directed to FIGURE 3 of the drawings, it is seenthat the printed circuit assembly generally designated 25 and includinga base member 26 and conductor areas or terminals 2727 is arranged forinsertion into the receptacle assembly. As indicated, the individualterminal areas 2727 are arranged for making electrical contact with thecontact portion 18 of the individual contacts 1515. If desired, thereceptacle assembly may be provided with a key or other arrangement forpolarizing the assembly wherever desired.

In the apparatus of FIGURES 1-3, the individual tail portions 1717 ofthe contacts 1515 extend downwardly from the bottom of the under surfaceof the bottom Wall of the assembly. In the apparatus of FIG- URE 4,these individual contacts extend outwardly from one wall portion of theassembly. It is the design of this apparatus which provides theversatility enabling the disposition of the tail portion of the contactsin essentially any desired manner. For example, the bottom wall or webportion 19a is utilized as a base for the receptacle receiving cavity,and also as an abutment surface for the lower portion of the individualcontacts, such as between the tail portion 17 and the shank portion 17a.This portion of the contact also provides a retaining lug for aid inassembly. Thus, the lower connecting web of the assembly enables a Wideversatility of contact disposition together with a maximum insertiondepth for the card being received within the assembly. Since thecontacts are generally disposed externally of the bottom web portion19a, it will be appreciated that this bottom web is not being utilizedto support or retain these contacts in molded-in configurations, butrather is used as an abutment wall only.

It will be observed that the inter-connecting portion 18 of the contacts15 commences at the radius or arcuate portion 21, for example, as shownin FIGURE 4. This arcuate portion provides fulcrum for deflection orflexure of the contacts and provides a maximum lever arm length betweenthe arcuate fulcrum and the actual area of contact. This long lever armprovides a maximum deflection of the contact relative to the lengththereof, and thus a wide variety of printed circuit boards havingsubstantial tolerances may be received within the receptacle cavity.

The versatiiity of this design is accordingly broad and substantial. Inaddition to accepting a relatively wide range of circuit boards, thereceptacle may be made in either a single or double sided configuration,the double sided configuration being shown herein. In addition, theoppositely disposed contacts can be used in connection with the platedthrough holes of a circuit board to provide for redundant contactfeatures. The tail portion of the contact can be infinitely varied intheir disposition, this variation being substantially within degrees, inaccordance with the bottom surface of the device. In addition, asillustrated in FIGURE 4, the tail portions 22 may extend outwardly fromone side of the connector assembly. If desired, the individual contactscan be staggered by suitable arrangement of the contact receivingchannels in the assembly. Furthermore, since reasonably good dielectricmaterials may be employed along the outer panel areas, it has been foundthat relatively thin sheets of dielectric can be employed and permit useup through the area of 15,000 volts for a relatively thin connectordevice. Also a reinforcement plate may be disposed along the bottom ofthe connector assembly.

It will be appreciated that this receptacle connector assembly may bemade of any desired length and width, it being recalled that the widthis at a practical minimum for the acceptance of the various contactsemployed. Furthermore, the length may be made consistent with therequirements of the printed circuit board which is to be acceptedtherein. Thus, modified forms of structure or contact arrangement may beemployed by utilizing certain of the features of this apparatus.

It will, of course, be understood that various changes may be made inthe form, details, arrangements and proportions of the parts withoutdeparting from the scope of the invention as set forth in the appendedclaims.

What is claimed is:

1. A connector device for arranging electrical contact to an electricaldevice having externally disposed contact terminals, said connectordevice comprising:

(a) receptacle frame means having a pair of end walls and a pair of sidewalls extending between oppositely disposed terminal ends of said endWalls, said walls forming a receptacle for an electrical device havingexternally disposed contact terminals;

(b) each of said side walls having a plurality of contact receivingchannels with generally parallel disposed axes formed along the innerand outer surfaces thereof, each of said channels having a certainpredetermined depth and terminating in a generally arcuate outer tipadjacent the top edge surfaces of said side walls;

(c) a plurality of contacts disposed along said channels, each contactcomprising an externally disposed tab portion, an inner leg connectingportion disposed within said receptacle, an outer shank portion disposedalong said outer surface between said tab and said inner leg connectingportions, and an arcuately formed coupling segment joining said innerleg and outer shank portions, said coupling segment having an innerradius substantially equal to the outer radius of said generally arcuateouter tip and forming a fulcrum point for said inner leg portion.

2. The connector device as defined in claim 1 being particularlycharacterized in that said contacts are formed of a flexible metallicconductor.

3. The connector apparatus as defined in claim 2 being particularlycharacterized in that said contacts are formed of beryllium copper.

4. The connector apparatus as defined in claim 1 being particularlycharacterized in that cover panel means are secured to the outersurfaces of said side walls to envelop said outer shank portions.

5. The connector device as defined in claim 1 being particularlycharacterized in that the depth of said outer channels is substantiallyequal to the thickness of the shank portion of the contacts.

6. The connector device as defined in claim 1 being particularlycharacterized in that said inner leg portion has a tip end zone withreverse curvature extending away from said cavity and toward said sidewall.

7. A connector device for printed wiring cards comprising:

(a) a receptacle frame means having a bottom wall, a

pair of end walls secured to said bottom wall, and a pair of side wallsextending along opposite edges of said bottom wall and between said endwalls and disposed between said end walls, said walls forming a printedwiring card receptacle;

(b) each of said walls having a plurality of contact receiving channelswith generally parallelly disposed axes formed along the inner and outersurfaces thereof, each of said channels having a certain predetermineddepth and terminating in a generally arcuate outer tip;

(c) a plurality of contacts disposed along said grooves, each comprisingan externally disposed tab portion, an inner leg connecting portiondisposed within said receptacle, an outer shank portion disposed alongsaid outer surface between said tab and said inner leg connectingportions, and an arcuately formed coupling segment joining said innerleg and outer shank portions, said coupling segment having an innerradius substantially equal to the outer radius of said generally acuatetip and forming a fulcrum point for said inner leg portion.

8. The connector device as defined in claim 7 being particularlycharacterized in that said side walls are spaced apart a distanceslightly greater than the thickness dimension of the printed wiring cardto be received therein.

9. The connector device as defined in claim 7 being particularlycharacterized in that said contacts comprise an externally disposed tabportion, an outer shank portion, an inner leg connecting portion, andfirst and second coupling segments, said first coupling segment havingan arcuate configuration and extending between said inner leg and outershank portions, and having an inner radius substantially equal to theouter radius of said generally arcuate outer tip to form a fulcrum pointfor said inner leg portion, said second coupling segment extendingbetween said externally disposed tab portion and said outer shankportion, and having One side thereof arranged in abutting contact withsaid bottom wall.

10. The connector device as defined in claim 1 being particularlycharacterized in that said generally arcuate outer tip is disposed inrecessed relationship below the top of said side walls.

References Cited UNITED STATES PATENTS 2,937,357 5/1960 Kennedy 339176X2,953,765 9/1960 Greasley 339-17 FOREIGN PATENTS 663,398 5/1963 Canada.

MARVIN A. CHAMPION, Primary Examiner.

J. R. MOSES, Assistant Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No.3,399,377 August 27, 1968 Herbert B. Warzecka It is certified that errorappears in the above identified patent and that said Letters Patent arehereby corrected as shown below:

Column 4, line 38, "parallel" should read parallelly Column 5, line 6,after "said" insert side line 21, "acuate" should read arcuate Signedand sealed this 27th day of January 1970.

(SEAL) Attest:

Edward M. Fletcher, Jr.

Attesting Officer Commissioner of Patents WILLIAM E. SCHUYLER, JR.

